There's a take-off of the industry slogan, "Beef: It's What's For Dinner" - "Beef: It's What's Rotting in Your Colon." I saw this on a shirt once with some friends and I was such the party pooper--no pun intended--explaining to everyone that meat is fully digested in the small intestine, and never makes it down into the colon. It's no fun hanging out with biology geeks.

But I was wrong!

It's been estimated that with a typical Western diet, up to 12 grams of protein can escape digestion, and when it reaches the colon, it can be turned into toxic substances like ammonia. This degradation of undigested protein in the colon is called putrefaction, so a little meat can actually end up putrefying in our colon. The problem is that some of the by-products of this putrefaction process can be toxic.

It's generally accepted that carbohydrate fermentation--the fiber and resistant starches that reach our colon--results in beneficial effects because of the generation of short-chain fatty acids like butyrate, whereas protein fermentation is considered detrimental. Protein fermentation mainly occurs in the lower end of colon and results in the production of potentially toxic metabolites. That may be why colorectal cancer and ulcerative colitis tends to happen lower down--because that's where the protein is putrefying.

Probably the simplest strategy to reduce the potential harm of protein fermentation is to reduce dietary protein intake. But the accumulation of these toxic byproducts of protein metabolism may be attenuated by the fermentation of undigested plant matter. In my video, Bowel Wars: Hydrogen Sulfide vs. Butyrate, you can see a study out of Australia showed that if you give people foods containing resistant starch you can block the accumulation of potentially harmful byproducts of protein metabolism. Resistant starch is resistant to small intestine digestion and so it makes it down to our colon where it can feed our good bacteria. Resistant starch is found in cooked beans, split peas, chickpeas, lentils, raw oatmeal, and cooled cooked pasta (like macaroni salad). Apparently, the more starch that ends up in the colon, the less ammonia that is produced.

Of course, there's protein in plants too. The difference is that animal proteins tend to have more sulfur-containing amino acids like methionine, which can be turned into hydrogen sulfide in our colon. Hydrogen sulfide is the rotten egg gas that may play a role in the development of the inflammatory bowel disease, ulcerative colitis (see Preventing Ulcerative Colitis with Diet).

The toxic effects of hydrogen sulfide appear to be a result of blocking the ability of the cells lining our colon from utilizing butyrate, which is what our good bacteria make from the fiber and resistant starch we eat. It's like this constant battle in our colon between the bad metabolites of protein, hydrogen sulfide, and the good metabolites of carbohydrates, butyrate. Using human colon samples, researchers were able to show that the adverse effects of sulfide could be reversed by butyrate. So we can either cut down on meat, eat more plants, or both.

There are two ways hydrogen sulfide can be produced, though. It's mainly present in our large intestine as a result of the breakdown of sulfur-containing proteins, but the rotten egg gas can also be generated from inorganic sulfur preservatives like sulfites and sulfur dioxide.

Sulfur dioxide is used as a preservative in dried fruit, and sulfites are added to wines. We can avoid sulfur additives by reading labels or by just choosing organic, since they're forbidden from organic fruits and beverages by law.

More than 35 years ago, studies started implicating sulfur dioxide preservatives in the exacerbation of asthma. This so-called "sulfite-sensitivity" seems to affect only about 1 in 2,000 people, so I recommended those with asthma avoid it, but otherwise I considered the preservative harmless. I am now not so sure, and advise people to avoid it when possible.

Cabbage family vegetables naturally have some sulfur compounds, but thankfully, after following more than a hundred thousand women for over 25 years, researchers concluded cruciferous vegetables were notassociated with elevated colitis risk.

Because of animal protein and processed food intake, the standard American diet may contain five or six times more sulfur than a diet centered around unprocessed plant foods. This may help explain the rarity of inflammatory bowel disease among those eating traditional whole food, plant-based diets.

There's a take-off of the industry slogan, "Beef: It's What's For Dinner" - "Beef: It's What's Rotting in Your Colon." I saw this on a shirt once with some friends and I was such the party pooper--no pun intended--explaining to everyone that meat is fully digested in the small intestine, and never makes it down into the colon. It's no fun hanging out with biology geeks.

But I was wrong!

It's been estimated that with a typical Western diet, up to 12 grams of protein can escape digestion, and when it reaches the colon, it can be turned into toxic substances like ammonia. This degradation of undigested protein in the colon is called putrefaction, so a little meat can actually end up putrefying in our colon. The problem is that some of the by-products of this putrefaction process can be toxic.

It's generally accepted that carbohydrate fermentation--the fiber and resistant starches that reach our colon--results in beneficial effects because of the generation of short-chain fatty acids like butyrate, whereas protein fermentation is considered detrimental. Protein fermentation mainly occurs in the lower end of colon and results in the production of potentially toxic metabolites. That may be why colorectal cancer and ulcerative colitis tends to happen lower down--because that's where the protein is putrefying.

Probably the simplest strategy to reduce the potential harm of protein fermentation is to reduce dietary protein intake. But the accumulation of these toxic byproducts of protein metabolism may be attenuated by the fermentation of undigested plant matter. In my video, Bowel Wars: Hydrogen Sulfide vs. Butyrate, you can see a study out of Australia showed that if you give people foods containing resistant starch you can block the accumulation of potentially harmful byproducts of protein metabolism. Resistant starch is resistant to small intestine digestion and so it makes it down to our colon where it can feed our good bacteria. Resistant starch is found in cooked beans, split peas, chickpeas, lentils, raw oatmeal, and cooled cooked pasta (like macaroni salad). Apparently, the more starch that ends up in the colon, the less ammonia that is produced.

Of course, there's protein in plants too. The difference is that animal proteins tend to have more sulfur-containing amino acids like methionine, which can be turned into hydrogen sulfide in our colon. Hydrogen sulfide is the rotten egg gas that may play a role in the development of the inflammatory bowel disease, ulcerative colitis (see Preventing Ulcerative Colitis with Diet).

The toxic effects of hydrogen sulfide appear to be a result of blocking the ability of the cells lining our colon from utilizing butyrate, which is what our good bacteria make from the fiber and resistant starch we eat. It's like this constant battle in our colon between the bad metabolites of protein, hydrogen sulfide, and the good metabolites of carbohydrates, butyrate. Using human colon samples, researchers were able to show that the adverse effects of sulfide could be reversed by butyrate. So we can either cut down on meat, eat more plants, or both.

There are two ways hydrogen sulfide can be produced, though. It's mainly present in our large intestine as a result of the breakdown of sulfur-containing proteins, but the rotten egg gas can also be generated from inorganic sulfur preservatives like sulfites and sulfur dioxide.

Sulfur dioxide is used as a preservative in dried fruit, and sulfites are added to wines. We can avoid sulfur additives by reading labels or by just choosing organic, since they're forbidden from organic fruits and beverages by law.

More than 35 years ago, studies started implicating sulfur dioxide preservatives in the exacerbation of asthma. This so-called "sulfite-sensitivity" seems to affect only about 1 in 2,000 people, so I recommended those with asthma avoid it, but otherwise I considered the preservative harmless. I am now not so sure, and advise people to avoid it when possible.

Cabbage family vegetables naturally have some sulfur compounds, but thankfully, after following more than a hundred thousand women for over 25 years, researchers concluded cruciferous vegetables were notassociated with elevated colitis risk.

Because of animal protein and processed food intake, the standard American diet may contain five or six times more sulfur than a diet centered around unprocessed plant foods. This may help explain the rarity of inflammatory bowel disease among those eating traditional whole food, plant-based diets.

Hibiscus tea has been found to be as effective at lowering blood pressure as a leading hypertension drug without the potential side-effects (which include everything from lack of strength to impotence, including rare cases of potentially fatal liver damage). Hibiscus, though, may have adverse effects of its own.

As I've reviewed previously in Plant-Based Diets: Oral Health, people who eat plant-based diets appear to have superior periodontal health, including less gum disease and fewer signs of inflammation, like bleeding. However, they also have twice the prevalence of dental erosions, areas on the teeth where the enamel has thinned due to more frequent consumption of acidic fruits and vegetables. Therefore, after we eat something like citrus, we should swish our mouths with water to clear the acid from our teeth.

This includes beverages. I'm a big fan of hibiscus tea, but it's not called "sour tea" for nothing. In a study highlighted in my video, Protecting Teeth from Hibiscus Tea, researchers at the University of Iowa dental school tested 25 different popular teas and found two with a pH under 3 (as acidic as orange juice or coca cola): Tazo's passion and Bigelow's red raspberry, both of which contain hibiscus as their first ingredient.

To see if these teas could actually dissolve teeth, the researchers took 30 extracted molars from people and soaked them in different teas. And indeed, out of the five teas tested, the greatest erosion came from the tea with the most hibiscus. The researchers left the tooth sitting in the tea for 25 hours straight, but this was to simulate a lifetime of exposure. The bottom line is that herbal teas are potentially erosive, particularly fruity and citrusy teas like hibiscus. To minimize the erosive potential, we can use a straw to drink the beverage. And as I mentioned above, after consuming an acidic food or drink we should also rinse our mouth with water to help neutralize the acid.

In 2013, Maryland became the first state to ban the feeding of an arsenic-containing drug to chickens. This arsenic-containing drug is used to control parasites and gives chicken meat an "appealing pink color." In 2011, the FDA found that the livers of chickens fed this drug had elevated levels of inorganic arsenic, a known human carcinogen. In response, the drug's manufacturer, Pfizer, voluntarily pulled the drug off the U.S. market. However, it's still sold overseas--including to places that continue to export chicken back to us--and a similar arsenic-containing drug for use in poultry is still available in the United States. The Maryland ban was still some help, though; it kept Maryland farmers from using stockpiles of the drug.

How much arsenic gets into the actual meat and not just the internal organs? We didn't know until recently. In a study highlighted in my video, How Many Cancers Caused by Arsenic-Laced Chicken?, researchers at the Johns Hopkins School of Public Health coordinated the purchase of chicken breasts off grocery store shelves in ten cities across the country. They found that 70% of the samples of chicken meat from poultry producers that didn't prohibit arsenic drugs were contaminated with the cancer-causing form of arsenic at levels that exceeded the safety thresholds originally set by the FDA (before the FDA relented and admitted that there's really no safe level of this kind of arsenic).

When the drug was first approved, scientists believed that its organic arsenic base would be excreted unchanged (organic arsenic is much less dangerous than inorganic arsenic). Guess what appears to convert the drug into the carcinogenic form? Cooking. When chicken meat is cooked, levels of the arsenic-containing drug go down and levels of carcinogenic arsenic go up, suggesting the drug may degrade into the cancer-causing inorganic arsenic form during cooking.

How much cancer are we talking about? If we estimate that about three-quarters of Americans eat chicken, then the arsenic in that chicken has potentially been causing more than 100 cases of cancer every year. The John Hopkins researchers conclude that "eliminating the use of arsenic-based drugs in [poultry and pig] production could reduce the burden of arsenic-related disease in the U.S. population."

Arsenic-containing drugs fed to chickens is one of the ways arsenic gets into rice. When we feed arsenic to chickens, the resulting arsenic-bearing poultry manure is introduced to the environment, soil, and water, and rice sucks it up from contaminated soil and can transfer it to people who don't even eat chicken. There is massive environmental contamination from the poultry industry; nearly two million pounds of arsenic has been poured into the environment every year by the U.S chicken industry alone.

We're even seeing arsenic in foods sweetened with organic brown rice syrup. It reminds me of the arsenic in apple juice story. Although the U.S. made lead and arsenic-based pesticides illegal years ago, they still persist in the soil, so even organic products are not immune.

There are other sources of arsenic (such as naturally occurring arsenic deposits), but arsenic-containing poultry drugs have been deliberately administered to animals intended for human consumption for 70 years. Consequently, exposures resulting from use of these drugs are far more controllable than are exposures from environmental sources. And the good news is that, thanks to a lawsuit from the Center for Food Safety and other consumer groups, three out of the four arsenic-containing drugs fed to poultry have been officially pulled from the market.

I've previously addressed this issue in my video Arsenic in Chicken. It's nice to see there's been some progress!

The antibiotics the poultry industry continues to feed chickens present another public health hazard. See my videos:

Phytate is a compound found in beans, grains, nuts and seeds. The average daily intake of phytate in vegetarian diets is about twice that of those eating mixed diets of plant and animal foods, which may help explain their low cancer rates. Aside from helping to prevent cancer, dietary phytate has been reported to help prevent kidney stone formation, protect against diabetes mellitus, dental cavities, and heart disease.

Do all these potentially beneficial effects sound too good to be true? Are there other examples of compounds made by plants that can have benefits across multiple diseases? Why yes! Aspirin, for example, which is found throughout the plant kingdom may also account for a variety of plant-based benefits (See Aspirin Levels in Plant Foods).

But of all the things phytates can do, the anticancer activity of phytate (also known as phytic acid, IP6, or inositol hexaphosphate), is considered one of its most important beneficial activities. Dietary phytates are quickly absorbed from the gastrointestinal tract and rapidly taken up by cancer cells throughout the body, and have been shown to inhibit the growth of all tested cancerous cell lines in vitro. Phytates have been shown to inhibit the growth of human leukemia cells, colon cancer cells, both estrogen receptor-positive and negative breast cancer cells, voicebox cancer, cervical cancer, prostate cancer, liver tumors, pancreatic, melanoma, and muscle cancers. All at the same time not affecting normal cells. That's the most important expectation of a good anticancer agent: the ability to only affect cancerous cells and to leave normal cells alone.

In my video, Phytates for Rehabilitating Cancer Cells, you can see how leukemia cells taken from cancer patients are killed by phytates, whereas normal bone marrow cells, are spared. This may explain why bean extracts kill off colon cancer cells in vitro, but leave normal colon cells alone.

What are the mechanisms of action by which phytates battle cancer? In other words, how do phytates fight? How don't they fight? Phytate targets cancer through multiple pathways, a combination of antioxidant, anti-inflammatory, immune-enhancing activities, detox, differentiation, and anti-angiogenesis. In other words, phytate appears to affect all the principal pathways of malignancy.

The antioxidative property is one of the most impressive characteristics of phytate. In fact that's why the meat industry adds phytates to meat to prevent the fat oxidation that begins at the moment of slaughter. Phytates can also act on our immune functions by augmenting natural killer cell activity, the cells in our body that hunt down and dispose of cancer cells, as well as neutrophils, which help form our first line of defense. And then phytates starve tumors as more of a last line of defense. Not only can phytates block the formation of new blood vessels that may be feeding tumors, but disrupt pre-formed capillary tubes, indicating that phytates may not just help blockade tumors, but actively cut off existing supply lines.

What's really remarkable about phytate, though, is that unlike most other anti-cancer agents, it not only causes a reduction in cancer cell growth but also enhances differentiation, meaning it causes cancer cells to stop acting like cancer cells and go back to acting like normal cells. You can see this with colon cancer cells for example. In the presence of phytates, human colon cancer cells mature to structurally and behaviorally resemble normal cells. And this has been demonstrated in leukemia cells, prostate cancer, breast cancer, and muscle cancer cells as well.

Fifteen million pounds of food dyes are sold every year in the U.S. Why? Foods "are artificially colored to make unattractive mixtures of basic ingredients and food additives acceptable to consumers." Food colorings are added to countless processed food products to "conceal the absence of fruits, vegetables, or other ingredients and to make the food appear better or of greater value than it is." Otherwise cherry popsicles might actually look as if they had no cherries in them!

I've talked about the role of food dyes in causing ADHD symptoms in kids (See Food Dyes and ADHD), but what about their role in cancer?

Due to cancer concerns, Red dye #1 was banned in 1961. Red #2 was banned in 1976, and Red #4 was banned soon after. But what about Red No. 3, used today in everything from sausage to maraschino cherries? It was found to cause DNA damage in human liver cells in vitro, comparable to the damage caused by a chemotherapy drug whose whole purpose is to break down DNA, but Red No. 3 was also found to influence children's behavior over 30 years ago and to interfere with thyroid function over 40 years ago. Why is it still legal?

By 1985, the FDA had already postponed action on banning the Red No. 3 twenty-six times, even though the Acting Commissioner of the FDA said Red No. 3 was "of greatest public health concern," imploring his agency to not knowingly allow continued exposure (at high levels in the case of Red No. 3) of the public to "a provisionally listed color additive that has clearly been shown to induce cancer while questions of mechanism are explored. The credibility of the Department of Health and Human Services would suffer if decisions are not made soon on each of these color additives." That was over 30 years ago. (To see the 1985 article published in the New York Times, check out my video, Red no. 3, Coloring to Dye for).

At the end of the day, industry pressure won out. While FDA scientists and FDA commissioners have recommended that the additive be banned, there has been tremendous pressure to delay the recommendations from being implemented.

In 1990, concerned about cancer risk, the FDA banned the use of Red No. 3 in anything going on our skin, but it remained legal to continue to put it in anything going in our mouths. The FDA also said they planned to end all other remaining uses of Red No. 3, lamenting that the cherries in 21st century fruit cocktail "could well be light brown."

But over 20 years later it's still in our food supply. After all, the agency estimated that the lifetime risk of thyroid tumors in humans from Red No. 3 in food was at most one in a hundred thousand. Based on the current U.S. population that's 3,000.

Used as a coloring agent in products ranging from colas and beer to gravies and soy sauce, caramel coloring may be the world's most widely consumed food coloring. It helps grocery stores sell more than a billion servings of food and beverages a day. Unfortunately, the manufacturing of certain artificial caramel colorings can lead to the formation of carcinogens such as 4-methylimidazole, which causes cancer in mice but not rats (or at least, not male rats). However, it is unclear whether humans are more like mice or rats in terms of their response to the carcinogen.

To be safe, California officially listed it as a carcinogen and started requiring warning labels on soft drinks containing more than 29 micrograms per serving. The soft drink industry was unsuccessful in opposing the action, so they were forced to reduce carcinogen levels in their products--but only in California. Buy Coke anywhere else, and it may have up to five times the limit (See Is Caramel Color Carcinogenic?).

In my videos Phosphate Additives in Meat Purge and Cola and Phosphate Additives in Chicken, I talked about the danger of phosphate and phosphate additives, and how phosphates are often added to chicken and turkey to help preserve the meat. But how often is poultry injected with phosphates? The vast majority of chicken products (more than 90%) were found to contain these additives. However, most packages did not list the additives on their label.

Sometimes they call the phosphate additives "flavorings" or "broth," and sometimes the labels don't say anything at all. In the video, How to Avoid Phosphate Additives, you can see the different ways phosphate additives have been listed (if they are listed at all) on ingredient labels. I'd recommend minimizing one's intake of anything with the four letters: "phos". These additives are also used in junk foods and fast food. Some products have phosphorus and aluminum additives. We see this a lot in processed cheeses. One grilled cheese sandwich may exceed the World Health Organization's provisional tolerable daily intake of aluminum by 428%. (I've previously touched on the aluminum in cheese in Aluminum in Vaccines vs. Food). More concerning, though, are the levels of lead in some venison (Filled Full of Lead) and mercury in tuna (The Effect of Canned Tuna on Future Wages).

The food industry no longer has to list phosphorus content on the nutrition facts label. There have been calls from the public health community to mandate that phosphorus content of foods be included back on the nutrition facts label, but I'm not holding my breath.

All these studies bring home the same strong message, "phosphorus-containing additives are present in most meat products and significantly increase the phosphorus content. Moreover, the lack of this information in the Nutrition Facts labels and even in nutrition databases prevents patients and dietitians from accurately estimating the phosphorus content of their food and their daily intake."

In my video Phosphate Additives in Meat Purge and Cola, I talked about the danger of phosphorus additives in food. However, when surveyed, most future medical professionals were insufficiently aware--in fact, two-thirds had no clue--of the risks related to prolonged high dietary phosphate intake. Even if they knew it was a problem, they didn't know which foods had added phosphates. 99% knew that sugar was added to soda, but only 7% knew that phosphates were added. I bet even fewer knew that it's injected into most packages of meat.

Though this practice remains banned in Europe, 11 different phosphate salts are currently allowed to be injected into meat and poultry in the United States. This despite the fact that phosphate is considered an arterial toxin--causing our arteries to stiffen up within just two hours of consumption. Phosphate additives may also make poultry more dangerous from a food safety standpoint.

Phosphate additives may increase the number of Campylobacter bacteria in chicken exudates. Chicken exudate is the same as poultry purge (colloquially known as chicken "juice"), "the fluid that seeps out from processed poultry carcasses and is often found to be contaminated with considerable numbers of Campylobacter bacteria. It is comprised of water, blood, fats, and other materials added to the poultry during processing." If chicken isn't injected with phosphate, the exudates seeping into the package may grow about 100 Campylobacter bacteria. But, add some phosphate to the carcass, and up to a hundred million bacteria may grow.

Why does adding phosphate to poultry increase the number of Campylobacter bacteria? It may be because phosphates increase the survival of Campylobacter--by 100 fold or more. The infectious dose for Campylobacter has been shown to be as little as 500 organisms. How much might there be in chicken? 100,000 can be easily recovered from washes of whole chicken carcasses.

So what does a million times more food-poisoning bacteria mean for the risk to consumers? A mere hundred fold increase in these fecal matter bacteria can mean a thirty fold difference in the number of human outbreaks of Campylobacter, which can leave patients paralyzed (see my video Poultry and Paralysis). But, if the poultry industry doesn't add phosphates, how are they (in their words) going to "enhance the moisture absorbance, color, and flavor of the meat and reduce product shrinkage?"

In my video, Treating Kidney Failure Through Diet, I profiled research suggesting that the use of a plant-based diet for patients with kidney failure would be beneficial. An important function of our kidneys is to filter out excess phosphorus from our bloodstream, so a decline in kidney function can lead to the build-up of phosphorus in our bodies. This in turn can cause something called metastatic calcification, where our heart valves and muscles and other parts of the body can buildup mineral deposits, eventually potentially resulting in bad things like skin necrosis, gangrene, and amputations. Therefore, controlling dietary phosphorus intake is the lynchpin of successful prevention of metastatic calcification. While both plant foods and animal foods have phosphorus, our bodies seem better able to handle phosphorus excretion from plants, so a plant-based diet may help protect against this dreadful condition.

However, we're beginning to realize that absorbing too much phosphorus isn't good for anyone, even those with healthy kidneys. Having high levels in our blood has been found to be an independent predictor of heart attacks and mortality in the general population, increasing the risk not only of kidney failure, but also of heart failure, heart attacks, coronary death, and overall death. Dietary intake of phosphate is an important matter not just for persons with kidney disease, but for everybody. It's thought to cause damage to blood vessels, to accelerate the aging process, and even, potentially, to hurt our bones by contributing to osteoporosis via a disruption of hormonal regulation. The estimated average requirement of phosphorus is less than 600 mg a day, but the estimated average intake in the United States is nearly twice that. How do we stay away from too much of the stuff?

In the video, Phosphate Additives in Meat Purge and Cola, we can see the different levels of phosphorus in different foods. It looks like many plant foods have as much phosphorus as many animal foods. So why are plant-based diets so effective in treating kidney failure patients? Because most of the phosphorus in plant foods is found in the form of phytic acid, which we can't digest. Therefore, while plant and animal foods may have similar phosphate contents, the amount that is bioavailable differs. In plant foods, the bioavailability of phosphates is usually less than 50%, while the bioavailability of most animal products is up around 75%.

So when we adjust for how much actually gets into our system, plant foods are significantly better. It's like the absorption of heme and non-heme iron: our bodies can protect themselves from absorbing too much plant-based iron, but can't stop excess muscle and blood-based (heme) iron from animals slipping through the intestinal wall (see my video Risk Associated With Iron Supplements).

The worst kind of phosphorus is in the form of phosphate additives (which are absorbed nearly 100%) that are added, for example, to cola drinks. Why is phosphate added to cola? Without the added phosphate, so many glycotoxins would be produced that the beverage would turn pitch black (see my video on Glycotoxins). Thus, cola drinks owe their brown color to phosphate.

Phosphate additives play an especially important role in the meat industry, where they are used as preservatives for the same reason: to enhance a meat product's color. Just like the dairy industry adds aluminum to cheese, the meat and poultry industries "enhance" their products by injecting them with phosphates. If one looks at meat industry trade journals and can get past all the macabre ads for "head dropping robots for the kill floor," you'll see all ad after ad for injection machines. Why? Because of "increased profitability." Enhanced meats have better color and less "purge."

Purge is a term used to describe the liquid that seeps from flesh as it ages. Many consumers find this unattractive, so the industry views phosphate injection as a win-win. When chicken is injected with phosphates, the "consumer benefits through the perception of enhanced quality," and the processor benefits from increased yield because they just pump it up with water and they sell it by the pound. The problem is that it can boost phosphorus levels in meat nearly 70%, a "real and insidious danger" not only for kidney patients, but for us all.